32 



BULLETIN 1490, U. S. DEPARTMENT OE AGRICULTURE 



and should be overcome by educational propaganda. Weight for 

 weight, red or heartwood hickory is as strong as white or sapwood. 

 Closer utilization can be effected by larger use of heartwood. Some 

 manufacturers paint their stock, to overcome this trade prejudice. 

 Effective remedies include kiln-drying at high temperatures (180° 

 F. and over); steaming at 130° F. (this will not^ insure against 

 future attack) (46,47) ; and treatment with orthodichlorobenzene or a 

 mixture of kerosene and coal-tar creosote, after which the material 

 should be kept in quarantine a sufficient length of time to deter- 

 mine whether a second 

 treatment is required. 



Partially damaged 

 material which is too 

 valuable to be de- 

 stroyed should be sal- 

 vaged, when practi- 

 cable, by trimming off 

 and burning the sap 

 edges and other dam- 

 aged and infested 

 parts. 



POWDER POST CAUSED BY 

 PTINIDAE AND ANOBI- 

 IDAE 



This damage con- 

 sists of small holes 

 one-sixteenth to one- 

 eighth of an inch in 

 diameter and irregu- 

 lar burrows in the 

 wood of both soft- 

 woods and hardwoods 

 (fig. 30). The dam- 

 age is similar to that 

 caused by Lyctus bee- 

 tles, except that softwoods are also attacked and the defect occurs 23 in 

 the heartwood. Most injury by Ptinidae is caused to seasoned wood, 

 or logs that have been left lving in the woods too long. 



Fig. 35. — Powder-posted southern yellow pine boards 

 damaged by Hylotrapes bajulus 



POWDER POST CAUSED BY BOSTRICHIDAE 



This damage consists of circular holes one-eighth to three-eighths 

 of an inch in diameter and irregular longitudinal burrows filled with 

 frass, or with coarser dust in the sapwood and heartwood of hard- 

 woods, which does not fall out so readily. (Figs. 31 and 32.) 



These insects 24 attack freshly felled logs with the bark on. The 

 eggs are laid within the log near holes made by the adult beetles. 



Submerging the logs in the mill pond and prompt utilization will 

 prevent much loss. In the case of vehicle, handle, and similar 



23 This defect is caused by Xyletinus peltatus Harris, which attacks both hardwoods 

 and softwoods. 



24 Bostrichidae : Scobicia, Xylobiops, etc. 



